Polymeric vinyl chloride fiberforming compositions



UNITED STATES ATENT OFFICE POLYMERIC VINYL CHLORIDE FIBER- FORMING COMPOSITIONS George E. Ham, Dayton, Ohio, assignor to The Chemstrand Corporation, Decatur, Ala., a corporation of Delaware No Drawing. Application May 5, 1952, Serial No. 286,210

9 Claims. (Cl. 260-455) 1 This invention relates to new fiber-forming compositions. More particularly the invention is concerned with the production of new polyvinyl chloride compositions and articles produced tion is primaril concerned with improving the thermal stability of polyvinyl chloride, it is also applicable to improving the thermal stability of various copolymers of vinyl chloride, such as therefrom which have superior properties such 5 those containing up to 15% by weight of vinyl as improved stability to heat, etc., as hereinafter acetate, vinylidene chloride, acrylonitrile, methd cribed acrylonitrile, and methyl acrylate.

It is well-known to prepare polymeric materials Among the copolymers suitable in the practice from vinyl chloride and these materials are findof the present invention are those containing at ing greatly expanding usefulness. Fibers and least 90% of acrylonitrile and up to 10% of other other shaped articles of polyvinyl chloride have polymerizable mono-olefinic monomers copolybeen marketable because of the relatively low merizable therewith. Suitable mono-olefinic cost of vinyl chloride. However, polyvinyl chlomonomers include vinyl acetate, styrene, vinyl ride possesses several draw-backs which have chloride, vinylidene chloride, alpha-methyldiscouraged the use of shaped articles of polystyrene, alkyl acrylates, alkyl methacrylates, alkyl vinyl chloride in many-fields of application. For fumarates, alkyl maleates, wherein the alkyl example, polyvinyl chloride softens and shrinks groups have up to four carbon atoms, methacryloexcessively at elevated temperatures and when nitrile, the vinylpyridines, the alkyl substituted articles produced from polyvinyl chloride are used vinylpyridines, and the vinyl, allyl, isopropenyl for some time in the presence of heat they begin and methallyl substituted N-heterocyclic comto stiffen and become brittle. Hence the problem pounds. The copolymers may have copolymeris presented to provide a means for preparing high ized therein minor proportions of other monquality products of polyvinyl chloride having imomers for the purpose of developing specialized proved heat stability, particularly with respect properties, such as dye-receptivity. Comonomers to shrinkage. imparting the dye-receptivity property may be Accordingly, it is an object of the present invinylpyridine or other N -heterocyc1ic monomers. vention to provide new vinyl chloride composi- Fire-proof properties are developed when minor tions which are notobjectionable with respect proportions of vinylidene chloride are copolymerto thermal stability. A further object of the inized therewith. Vinyl chloroacetate may be used vention is to provide an improved low cost fiberas a third monomer and thereby the copolymer forming composition. Other objects and advanis made reactive with ammonia and amines and tages of the present invention will be apparent the resulting chemically treated polymer becomes from the description thereof hereinafter. dye-receptive.

While the present invention is described as it The acrylonitrile copolymers and the polyvinyl is primarily applicable to the manufacture of fichloride may be blended by a variety of procebers and filaments, it is to be understood that this dures. The finely divided polymers may be meis merely intended in an illustrative sense and chanically mixed and thereafter fabricated into the invention is not to be limited thereby, since fibers by conventional methods, for example, the the same is also applicable to the manufacture dissolution in suitable solvents and extrusion of of other shaped articles of polyvinyl chloride, the p p Solution through a e 0 Spinsuch as filmsjfoils, rods, threads, molded articles, Beret containmg & plurality of p tu es- F01- and theslike, g lowing the preparation of the fiber by extrusion It has been found, and the objects of the ininto asaseous medium aliquid medium a apted vention are in general accomplished by blending to remove the Solvent from the Continuous D 3- polyvinyl chloride with from two to 35% of a meric composition, the resulting fiber is then copolymer containing at least 90% by weight, i stretched, shrunk or otherwise subjected to physthe polymer molecule of acrylonitrile, and prefical Working heat-treatment deVelOp e erably in excess of 5 In t compositions of optimum fiber properties. The methods of fabrithe present invention, the polyvinyl chloride is eating and processing the fibers are not regarded present in an amount within the range of 65 to as part of this invention, except to the extent 98% by weight. Such blended compositions have that a wider variation in types of p c g s been found to be substantially improved with re- Possiblespect to their softening characteristics and are A preferred method of preparing a blended thus more stable to high temperatures than polycomposition involves the dispersing of the polyvinyl chloride alone. While the present inven-- meric components into a suitable solvent for both aesaice components. Suitable solvents are N,N-dimethylacetamide, DLN-dimethylformamide, gammabutyrolactone, nitromethane, dimethyl phosphite, and ethylene carbonate. Solutions in these solvents are spun into fibers by conventional methods.

Further details of the invention are set forth with respect to the following examples.

Example I mined at various temperatures employing a Fisher-Johns melting point block modified with a grid scale. The following shrinkage data were obtained:

Temperature: Percent shrinkage 85 C. 5 110 C 125 C. 140 C. 220 C 2'7 5 A zero strength temperature of 142 C. was obtained. The zero strength temperature was determined by contacting the fiber under slight tension with a heated rod of known temperatures.

A second solution containing 18% of polyvinyl chloride in dimethylacetamide was prepared and the resultant solution spun into fibers as outlined above. The fibers were then stretched 138% as described above and the following shrinkage data on the fibers thus obtained:

Temperature: Percent shrinkage 55 C 2.5 105 C 50 220 C 78 The zero strength temperatures for the polyvinyl chloride fiber without the acrylonitrile copolymer was 133 C.

It can be seen from the above data that the blending of a copolymer of acrylonitrile with the polyvinyl chloride increases the stability of the latter to heat. In addition, the percent shrinkage .of the polyvinyl chloride is greatly reduced at elevated temperatures.

Example II An 18% solids solution in vdimethylacetamide of a blend of 80% by weight of polyvinyl chloride and 20% of a copolymer of 95% acrylonitrile and 5% styrene was prepared. The resultant solution was spun and the fibers stretched as described in Example I. Shrinkage and zero strength temperature data on the fibers indicated a substantial improvement in thermal characteristics over polyvinyl chloride fibers.

Example III A 19% solids solution in dimethylacetamide of a blend of by weight of polyvinyl chloride and 20% of a copolymer of 95% acrylonitrile and 5% vinylidene chloride was prepared. The resultant solution was spun and the fibers stretched as described in Example I. The shrinkage and zero strength temperature data on the fibers were quite similar to those reported. in-Example I for the blended composition.

Fibers, films, and other shaped articles, produced from the compositions in accordance with the present invention, find wide use in the manufacture of such materials as seat covers, table covers, shower curtains, and the like, and many other articles where stability to heat is important. Many other advantages of the instant invention will .be apparent to those skilled in the art.

It is to be understood that changes and variations may be made without departing from the spirit and scope of the invention as defined in the appended claims.

I claim:

1. A fiber-forming composition which .comprises a blend of from 65 to 98% by weight of polyvinyl chloride. and from two to 35% by weight of a copolymer. comprising at 1east:90% by. weight of acrylonitrile and not more than 10% of a polymerizable mono-olefinic monomer copolymerizable therewith.

2. A fiber-forming claim 1 wherein the. vinyl acetate.

3. A fiber-forming claim 1 wherein the styrene.

4. Afiber-for-ming claim 1 wherein the vinylpyridine.

5. A fiber-forming claim 1 wherein the vinylidene chloride.

6. A fiber-forming claim 1 wherein the methyl methacrylate.

7. A fiber-forming composition which comprises-a blend of from 165 to'98%.by weight of polyvinyl chloride and from two to'35 by weight of a copolymer containing by weight in the polymer molecule,. 97% of .acrylonitrile and 2% of vinyl acetate.

8. A fiber-forming. composition which comprises a blend of 80% by weightof polyvinylchloride and 20% by weight ofa .copolymercontaining by weight inthe polymermolecule 92% of acrylonitrile and 3% of vinyl acetate.

9. A fiber-forming composition which comprises a blend of from 65to 98% by weight .of a polymer containing at least ,by weight of vinyl chloride and not more than 15 of another polymerizable mono-olefinic monomer and from two to 35% by weight of a copolymercomprising at least by weight of acrylonitrile and not more than 10% of a polymerizable mono-olefinic monomer copolymerizable therewith.

composition :as defined in mono-olefinic monomer is composition as defined in mono-olefinic monomer .is

- composition .as defined .in mono-olefinic monomer .is

composition asdefined in mono-.olefinic monomer .is

composition as defined in mono-olefinic monomer is References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,404,714 Latham July 23, 1946 2,646,417 Jennings July 21, 1953 

1. A FIBER-FORMING COMPOSITION WHICH COMPRISES A BLEND OF FROM 65 TO 98% BY WEIGHT OF POLYVINYL CHLORIDE AND FROM TWO TO 35% BY WEIGHT OF A COPOLYMER COMPRISING AT LEAST 90% BY WEIGHT OF ACRYLONITRILE AND NOT MORE THAN 10% OF A POLYMERIZABLE MONO-OLEFINIC MONOMER COPOLYMERIZABLE THEREWITH. 